Using laser technology, a group of archaeologists found the remains of a huge pre-Hispanic city in present-day Bolivia. He belonged to the Casarabe people, who lived in the Amazon basin between 500 and 1400 AD.
The discovery, made by archaeologists Heiko Prümers, Carla Jaimes Betancourt, José Iriarte, Mark Robinson and Martin Schaich, was published in the journal Nature.
The researchers used an airborne LiDAR (laser light detection and ranging technology), in which thousands of infrared laser pulses bounce off the ground every second. This revealed archaeological structures beneath dense vegetation.
In the settlements located in Llanos de Mojos, Bolivia, there was a network of roads, causeways, reservoirs and canals.
It was always thought that the Casarabe town was small, because there were few related settlements, but the discovery of this city sheds new light.
“Our results indicate that the settlement pattern of the Casarabe culture it represents a type of low-density tropical urbanism that had not been previously described in the Amazon,” the researchers point out in their study.
The huge city of the Casarabe people, found with laser technology
The Casarabe culture spread over an area of 4,500 square kilometers, and 189 large monumental sites, known as lomas, were found, in addition to 273 smaller places and 957 kilometers of canals and causeways.
“Excavations and bioarchaeology,” the experts point out, “indicate that the monumental sites were not unoccupied ceremonial centers, but they were inhabited throughout the year by farmers who grew a diversity of crops, with maize as the main staple food, and who met their protein needs by hunting and fishing.”
Prior to the recent find, the extent and architectural details of only a few mounds were known, due to difficulties in mapping sites in tropical forest environments. But the advances in technology expanded the knowledge of the Casarabe culture.
- The dimensions of human-made platforms.
- The elaboration of civic-ceremonial architecture.
- The presence, number and total area enclosed by the outermost polygonal enclosures.
- The number of straight roadways built leading to the site.
- And the scale of investment in water management infrastructure, including canal systems and water reservoirs.
“Within an hour’s walk, we can reach another settlement,” reveals archaeologist Prümers. “That is a sign that this region was very densely populated in pre-Hispanic times.”